While many of his protégés (Eric Clapton, former Rolling Stones guitarist Mick Taylor) have gone on to flashier careers, veteran bluesman John Mayall stakes out his place in history by perfecting the rock-infused 12-bar structure for diehard fans who eagerly pack in small spaces to hear him play. Tonight's show should be no exception, with a brand new band lineup and songs from the prolific guitarist's recently released 57th album.